I don't really think they can unless something drastic changes. You mention all these superstars returning, but when you look at some of the names you said were on their last run, how long will it really last. Ric can't win for the next 2 years, Mick will probably be off tv again, 3D might/probably will get released by then (if they get their contract soon enough), Cena will probably be champ again. So by 2010, you've pretty much gone back to the bad product WWE had about a year ago.
And TNA is a low budget show, they weren't meant to beat out WWE in ratings, but they can still survive and make some sort of profit even with losing ratings. I think it'll take some sort of fluke for them to go out of business.